Project Wrath Deckbuilder Dev Update #4

Critical updates:

• Added a 'Main Menu' button that can be clicked after death, so that game can be replayed without refresh/reopening.
• Fixed a bug where heal option could be clicked from the card upgrade panel.

Small updates:

• Portable Barrier - Base shield buffed
• Mischief And Magic - Added
• Mischievous Blade - Added
• Preemptive Strike - Added